\documentclass{standalone}
\usepackage{tikz} % Required for drawings
\usetikzlibrary{positioning,calc}

\newcommand{\easttowest}[4]{
\draw[-latex] (#1.east) -| ($ (#1.east) + (#3,0) $) |- node[near end, above]{#4} (#2.west);
}

\begin{document}
	\tikzstyle{box}=[draw, rectangle, minimum height=1.5cm, minimum width=3.5cm,align=center]
	
	\begin{tikzpicture}[font=\sffamily]
		\node[box] (server) at (2,0) {Map server (container) \\ \footnotesize{(0.1.0)} \\ \footnotesize{Apache-2.0}};

		\node[box] (docker) at (8,0) {Docker \\ \footnotesize{(1.6)} \\ \footnotesize{Apache-2.0}};
		\node[box] (postgresql) at (8,-2) {PostgreSQL \\ \footnotesize{(9.3)} \\ \footnotesize{PostgreSQL License}};
		\node[box] (postgis) at (8,-4) {PostGIS \\ \footnotesize{(2.1)} \\ \footnotesize{GPL-2.0}};
		\node[box] (osmosis) at (8,-6) {Osmosis \\ \footnotesize{(0.43.1)} \\ \footnotesize{GPL-3}};
		\node[box] (osm) at (8,-8) {OpenStreetMap \\ \footnotesize{(any dump)} \\ \footnotesize{ODbL}};

		\easttowest{server}{docker}{0.5}{{\footnotesize{usage}}}
		\easttowest{server}{postgresql}{0.5}{{\footnotesize{usage}}}
		\easttowest{server}{postgis}{0.5}{{\footnotesize{usage}}}
		\easttowest{server}{osmosis}{0.5}{{\footnotesize{usage}}}
		\easttowest{server}{osm}{0.5}{{\footnotesize{usage}}}

		\node[box] (tools) at (2,-10) {Map tools (Python) \\ \footnotesize{(0.1.0)} \\ \footnotesize{Apache-2.0}};
		\node[box] (psycopg) at (8,-10) {Psycopg \\ \footnotesize{(2.4.5)} \\ \footnotesize{LGPL-3.0}};
		\node[box] (gdal) at (8,-12) {GDAL \\ \footnotesize{(1.10)} \\ \footnotesize{MIT License}};
		\node[box] (numpy) at (8,-14) {NumPy \\ \footnotesize{(1.6.1)} \\ \footnotesize{BSD 3-Clause}};
		\node[box] (python) at (8,-16) {Python Std. Libary \\ \footnotesize{(2.7.3)} \\ \footnotesize{Python License}};

		\draw[-latex] (server) -- node[right]{\footnotesize{usage}} (tools);
		\easttowest{tools}{psycopg}{0.5}{{\footnotesize{dynamic}}}
		\easttowest{tools}{gdal}{0.5}{{\footnotesize{dynamic}}}
		\easttowest{tools}{numpy}{0.5}{{\footnotesize{dynamic}}}
		\easttowest{tools}{python}{0.5}{{\footnotesize{dynamic}}}
	\end{tikzpicture}
\end{document}
